Chapter 15, Problem 15.75AP

Interpretation Introduction

Interpretation:

Reason for coconut oil to exist as liquid at room temperature has to be explained.

Concept Introduction:

Melting point in fatty acids depends on factors as follows:

1. In saturated molecules, atoms are closely packed to form strong lattice structures thus do not break easily. Hence, they have higher melting point.

2. In unsaturated molecules, double bond tends to bend the molecule and restricts the close packing of molecule which in turn reduces melting point. Hence, melting point of fatty acids decreases with increase in double bonds.

3. Molecule with cis double bonds has higher melting point than trans double bonds. The cis-double bonds in unsaturated fatty acids put an inflexible “kink” in the carbon chain. The kink prevents the molecules from packing together as tightly as saturated fatty acids do.